Multi chamber flat pipe, heat exchanger, and use of a heat exchanger

ABSTRACT

The invention is based on a multi-chamber flat tube (V 1 -V 17 ) having at least two chambers ( 1, 2 ) for holding the flow of a fluid, produced by deforming a sheet-metal strip, in particular produced in a bending and/or folding and/or crimping process, in which a closed profile is formed by: opposite wide walls ( 4, 6 ) which are connected to one another by means of opposite narrow walls ( 5, 7 ) which form in each case one deformed region, with the wide and narrow walls forming outer sides of the profile, with a first wide wall ( 4 ) being formed by an inner section of the sheet-metal strip which is situated between side sections of the sheet-metal strip, and with a second wide wall ( 6 ) being formed by side sections, which are arranged to the sides of the inner section, of the sheet-metal strip, with the first and second wide walls ( 4, 6 ) being connected by means of a web ( 3 ) which separates at least two chambers and which forms an inner side of the profile and which is formed by an edge section ( 3 A,  3 B) of at least one of the side sections, with only one of the side sections having an edge section ( 3 A,  3 B) which runs continuously, in particular from an inner side, of the second wide wall ( 6 ) to, in particular an inner side, of the first wide wall ( 4 ) and is connected there in a cohesive manner, in particular by means of soldering, at a contact point ( 8 ), with the continuous edge section having at least two deformed sections ( 3 B. 1, 3 B. 2, 3 B. 3, 3 B. 4, 3 B. 5 ) and at least one of the deformed sections forming a contact surface ( 9 ) for an edge section ( 3 A) of the other side section. To improve a multi-chamber flat tube of said type, the invention provides the following possible measures, if appropriate in combination. In a first variant, that deformed section of the continuously running edge section ( 3 B) which forms the contact surface ( 9 ) may run obliquely or at right angles with respect to the second wide wall ( 6 ), and at least one further deformed section of the continuously running edge section ( 3 B) may run obliquely or at right angles with respect to that deformed section of the continuously running edge section ( 3 B) which forms the contact surface ( 9 ). In a second variant, that deformed section of the continuously running edge section ( 3 B) which forms the contact surface ( 9 ) may be one of a plurality of deformed sections which are arranged in a v-shape, s-shape, u-shape or o-shape or so as to be wound or folded. In a third variant, it is possible for the edge section ( 3 A) of the other side section not to have a deformed section and to be part, in particular of the first or second region, of the second wide wall ( 6 ). In a fourth alternative, the edge section ( 3 A) of the other side section may have only deformed sections (V 11 -V 14 ) which run at right angles or parallel to the second wide wall, in particular only deformed sections which are arranged in an i-shape or l-shape. The invention also encompasses a multi-chamber flat tube in which at least one of the chambers ( 1, 2 ) is formed by a plurality of walls, in particular two walls, and the web ( 3 ) has at least two of said walls, and at least one edge section ( 3 A) of the side sections is fixed to the web ( 3 ). The invention also encompasses a corresponding heat exchanger and a corresponding use of the heat exchanger.

The invention relates to a multi-chamber flat tube having at least two chambers for holding the flow of a fluid, produced by deforming a sheet-metal strip, in which a closed profile is formed by: opposite wide walls which are connected to one another by means of opposite narrow walls which form in each case one deformed region, with the wide and narrow walls forming outer sides of the profile, with a first wide wall being formed by an inner section of the sheet-metal strip which is situated between side sections of the sheet-metal strip, and with a second wide wall being formed by side sections, which are arranged to the sides of the inner section, of the sheet-metal strip, with the first and second wide walls being connected by means of a web which separates at least two chambers and which forms an inner side of the profile and which is formed by an edge section of at least one of the side sections, with only one of the side sections having an edge section which runs continuously from the second wide wall to the first wide wall, in particular the inner sides of said wide walls, and is connected there in a cohesive manner, in particular by means of soldering, at a contact point, with the continuous edge section having at least two deformed sections and at least one of the deformed sections forming a contact surface for an edge section of the other side section. The invention also relates to a heat exchanger having a flat tube of said type and to a use of the heat exchanger. The invention also relates to a multi-chamber flat tube having at least two chambers for holding the flow of a fluid, produced by deforming a sheet-metal strip, in which a closed profile is formed by: opposite wide walls which are connected to one another by means of opposite narrow walls which form in each case one deformed region, with the wide and narrow walls forming outer sides of the profile, with a first wide wall being formed by an inner section of the sheet-metal strip which is situated between side sections of the sheet-metal strip, and with a second wide wall being formed by side sections, which are arranged to the sides of the inner section, of the sheet-metal strip, with the first and second wide walls being connected by means of a web which separates at least two chambers and which forms an inner side of the profile. The invention also relates to a heat exchanger having a flat tube of said type and to a connection of the heat exchanger.

Multi-chamber flat tubes have proven to be increasingly attractive for use in a heat exchanger—for example as described in EP 1 213 555 B1—because such multi-chamber flat tubes can be provided so as to be comparatively thin-walled and therefore in a material-saving manner, and can furthermore be produced in a comparatively simple deformation process, for example in a bending process and/or a folding process and/or a crimping process—a deformation process of said type is described for example in U.S. Pat. No. 6,615,488 B2. The folding process described therein generates a multi-chamber flat tube of the so-called “B-type”, because the profile of the multi-chamber flat tube has a profile reminiscent of a B-shape. Another similar multi-chamber flat tube is described in EP 1 213 555 B1 and in EP 0 811 820 B1. In both multi-chamber flat tubes, edge sections of the two side sections which form the second wide wall are guided continuously from an inner side of the second wide wall to an inner side of the first wide wall, and are connected there by soldering at a contact point. It has been found that a multi-chamber flat tube of said so-called B-type still has room for improvement.

EP 1 225 408 A2 presents a multi-chamber flat tube of the type specified in the introduction, in which only one of the side sections has an edge section which runs continuously from an inner side of the second wide wall to an inner side of the first wide wall and is cohesively connected there at a contact point. The edge section has at least two deformed sections and at least one of the deformed sections forms a contact surface for an edge section of the other side section. Such a design of a multi-chamber flat tube of the B-type has proven, in terms of the configuration of the web, to be material-saving, though can still be improved, in particular with regard to the tensile action performed by the web.

The invention addresses this; it is an object of the invention to specify a multi-chamber flat tube in which in particular a tensile action of the web, the stability behavior and/or the compressive strength of the multi-chamber flat tube is improved and the multi-chamber flat tube can nevertheless be produced in a comparatively simple and cost-effective manner.

The object is achieved by means of the invention in a first part by means of a multi-chamber flat tube of the type specified first in the introduction, in which, according to the invention, different variants of features as per the characterizing part of claim 1 are provided, which may also be realized in combination with one another.

In a first variant, that deformed section of the continuously running edge section which forms the contact surface is formed so as to run obliquely or at right angles with respect to the second wide wall, and at least one further deformed section of the continuously running edge section is formed so as to run obliquely or at right angles with respect to that deformed section of the continuously running edge section which forms the contact surface.

In a second variant, that deformed section of the continuously running edge section which forms the contact surface is one of a plurality of deformed sections which are arranged in a v-shape, s-shape, u-shape or o-shape or so as to be wound or folded.

In a third variant, the edge section of the other side section does not have a deformed section and is part of the second wide wall.

In a fourth variant, the edge section of the other side section has only deformed sections which run at right angles or parallel to the second wide wall. In particular, in addition, the edge section of the other side section has only deformed sections which are arranged in an i-shape or 1-shape.

The invention has recognized that, by means of the above-stated variants individually or in combination, a new, advantageous geometry of a profile of the multi-chamber flat tube is realized, which geometry provides an increased level of compressive strength. This is obtained primarily in that the web is designed as a web which acts as a tension rod, in a way which is superior to the prior art. In particular, it is additionally possible for the edge sections which form the web to be formed by means of the deformed sections in such a way that the edge sections are in engagement with one another and/or are advantageously connected in a cohesive manner to a contact surface. According to the invention, the web is advantageously cohesively connected to the first wide wall. This results in an increased compressive strength, which is realized for the first time according to the invention, in the horizontal and vertical directions of the profile of the flat tube.

Advantageous refinements of the invention may be gathered from the subclaims and specify, in detail, advantageous possibilities for realizing the above-explained concept within the context of the set object and with regard to further advantages.

The contact point is preferably formed by means of a large-area contact region of a deformed section. It is possible in this way to realize a web which is fastened in a particularly secure manner to the inner side of the first wide wall. The same applies to a further preferred refinement, in which the contact point is formed by means of a contact region of a deformed edge between two deformed sections. In addition, said modification makes it possible to realize a web in which the tension rod action can at the same time be configured to be secure and flexible. A comparatively simple connection of the web in relation thereto can be obtained in that the contact point is formed by means of a contact region of an abutting edge of the continuously running edge section.

Furthermore, a level of strength of the web can be improved in that a cohesive connection, in particular soldered connection, is formed on the contact surface of the at least one of the deformed sections of the continuously running edge section and the edge section of the other side section, between the at least one of the deformed sections of the continuous edge section and the edge section of the other side section. This may be obtained in that the edge section and/or the deformed sections of the continuously running edge section are solder-plated on one side or two sides. In simpler cases, it is if appropriate sufficient to provide a sufficient solder reserve on the inner side of the first wide wall such that, during the soldering process, a sufficient solder quantity extends into the contact surface in order that the deformed section of the continuously running edge section and the edge section of the other side section are fixed to one another, or connected to one another by soldering, in a satisfactory manner.

The concept of the invention has proven to be advantageously applicable in the case of a multi-chamber flat tube, in which at least one of the chambers is formed by one wall. The wall thickness of a chamber may preferably be realized so as to be less than 0.2 mm. The concept of the invention may fundamentally also be implemented in a multi-chamber flat tube in which at least one of the chambers is formed by a plurality of walls, in particular two walls. Here, too, it has proven to be advantageous for a wall thickness of a wall to be less than 0.2 mm—the total wall thickness of a chamber having a plurality of walls is therefore advantageously less than a multiple of 0.2 mm; in the case of two walls, preferably less than 0.4 mm. A multi-walled multi-chamber flat tube may for example be formed by means of suitable winding arrangements of the sheet-metal strip. In one modification, it is also possible for two or more profiles to be arranged one inside the other so as to form a concentric wall arrangement.

In addition to the above-explained web which provides a tensile action, it is possible to provide one or more further webs of said type, or other webs, in the profile in order to form a multi-chamber flat tube having more than two chambers. It is preferably possible for further webs to be formed by folding in the first and/or second wide wall. The latter has proven to be a particularly simple measure for forming further webs.

It is fundamentally possible for the surfaces of a multi-chamber flat tube of the above-explained type to be formed in a wide variety of ways so as to be suitable for an application. It is for example possible for a tube outer surface and/or a tube inner surface to be smooth. A multi-chamber flat tube of said type has a particularly low flow resistance.

In another refinement which improves the heat exchanger function of the multi-chamber flat tube, it is possible for a tube outer surface and/or a tube inner surface to be structured. It has been found that a plurality of different types of structured elements are suitable for this purpose, in particular those which are selected from the group comprising: dimples, winglets, ribs.

A multi-chamber flat tube of the above-explained type has proven to be particularly reliable for conducting a fluid while having an increased compressive strength and under the special action of the web which provides the tension rod action as per the concept of the invention. In one particularly preferred refinement, the fluid may by a first fluid, in particular in the form of an exhaust gas and/or charge air. In the same way, a multi-chamber flat tube is also suitable for a second fluid, preferably a coolant, in particular a liquid-based coolant.

According to the concept of the invention, a multi-chamber flat tube of the above-described type is suitable for a heat exchanger for exchanging heat between a first fluid on the one hand, in particular an exhaust gas and/or charge air, and a second fluid on the other hand, in particular a coolant. Such a heat exchanger according to the invention has: a block for the separate and heat-exchanging guidance of the first and second fluids, having a number of flow ducts through which the first fluid can flow, a first chamber which holds the flow ducts and through which the second fluid can flow, and a housing in which the chamber and the flow ducts are arranged. According to the concept of the invention, a flow duct is, according to the invention, formed in the manner of a flat tube of the above-explained type.

The invention also encompasses a particularly preferred use of the heat exchanger according to the further independent claims, for example as a high-temperature or low-temperature heat exchanger—in both cases as, for example, an exhaust-gas heat exchanger or as a charge-air heat exchanger.

Furthermore, the heat exchanger as per the concept of the invention has also proven to be suitable for use as an oil cooler or as a refrigerant or coolant cooler.

The object explained in the first part of the introduction is also achieved by the invention, in a second part, by means of a multi-chamber flat tube of the type specified in the last part of the introduction, in which, according to the invention, as per the characterizing part of claim 19, at least one of the chambers is formed by a plurality of walls, and the web of at least two of said walls, and at least one edge section of the side sections is fixed to the web. Said part of the invention also follows the concept of a web which is formed with a comparatively high tensile strength in order to increase the compressive strength of the flat tube, with the compressive strength of the multi-chamber flat tube additionally being increased by means of the provision of a plurality of walls, in particular two walls.

Advantageous refinements of the invention may be gathered from the subclaims and specify, in detail, advantageous possibilities for realizing the above-explained concept with regard to a double-walled multi-chamber flat tube within the context of the set object and with regard to further advantages.

In one particularly preferred refinement, at least one of the chambers is wound with a plurality of walls, in particular two walls. In this refinement, the web also particularly advantageously has at least two walls which are formed as part of the winding. The multi-chamber flat tube can thereby be produced in a comparatively simple manner by deforming the sheet-metal strip, for example in a correspondingly configured winding process.

Two walls of the web may preferably be formed by means of a folded-in portion.

In a further particularly preferred refinement, it is possible for at least one of the chambers to be formed by a plurality of walls which are placed concentrically one inside the other. In said refinement, it is preferably possible for the web to have at least two walls which are formed as part of the walls which are placed one inside the other.

In one particularly preferred refinement of the second part of the invention, only one of the edge sections of the side sections, or particularly preferably none of the edge sections of the side sections, runs continuously from the second wide wall to the first wide wall, that is to say in particular the inner sides of the wide walls.

In a first modification of the particularly preferred refinement, it is possible for an edge section of at least one of the side sections to adjoin the web. In a particularly simple design, the edge section may in this respect abut with an abutment edge against the web.

In a second modification of the particularly preferred refinement, the web may be formed by an edge section of at least one of the side sections. The edge section may in this respect preferably bear with a contact surface against the web.

In a third modification of the particularly preferred refinement, the abutment edge of the edge section may also be exposed.

As an alternative to the particularly preferred refinement, an abutment edge of the edge section may be fixed to the inner side of the first wide wall. This is particularly advantageous for a multi-chamber flat tube which is formed by a plurality of walls which are placed concentrically one inside the other.

As has already been explained in connection with the first part of the invention, it is possible for an individual wall thickness to be preferably less than 0.2 mm and nevertheless for a compressive strength of the multi-chamber flat tube to be ensured. This is preferably improved in that a cohesive connection, in particular a soldered connection, is formed on one or more contact surfaces or points between walls.

As has already been explained in connection with the first part of the invention, it is possible for further webs to be formed, in particular by folding in the first and/or second wide wall. It is fundamentally possible for only tube outer surfaces and/or tube inner surfaces to be smooth or structured depending on the application. Furthermore, the invention encompasses a heat exchanger and a corresponding use of the heat exchanger, as can be gathered from the further independent claims.

Exemplary embodiments of the invention are now explained below on the basis of the drawing. Said drawing is intended to illustrate the exemplary embodiments not necessarily to scale; the drawing is in fact shown in schematized and/or slightly distorted form where appropriate for explanation. With regard to enhancements of the teaching which can be directly gathered from the drawing, reference is made to the relevant prior art. Here, it is to be taken into consideration that various modifications and changes relating to the shape and details of an embodiment may be carried out without departing from the general idea of the invention. The features of the invention disclosed in the description, in the drawing and in the claims can be essential both individually and also in combination for the refinement of the invention. Furthermore, all combinations of at least two of the features disclosed in the description, the drawing and/or the claims fall within the scope of the invention. The general idea of the invention is not restricted to the precise shape or the detail of the preferred embodiment shown and described below, or restricted to a subject matter which would be restricted in relation to the subject matter claimed in the claims. Where dimensional ranges are specified, values which fall within the specified limits are also intended to be disclosed as limit values and usable and claimable in any desired manner.

The drawing shows, in detail:

FIG. 1 shows the profile of a first embodiment of a multi-chamber flat tube as per the first variant of the first part of the invention, in which that deformed section of the continuously running edge section which forms the contact surface runs obliquely with respect to the second wide wall;

FIG. 2 shows the profile of a further embodiment of a multi-chamber flat tube as per the first variant of the first part of the invention;

FIG. 3 shows the profile of a further embodiment of a multi-chamber flat tube as per the first variant of the first part of the invention;

FIG. 4 shows the profile of a first embodiment of a multi-chamber flat tube as per the second variant of the first part of the invention, with a tension rod action being of comparatively soft or flexible configuration;

FIG. 5 shows the profile of a further embodiment of a multi-chamber flat tube as per the second variant of the first part of the invention;

FIG. 6 shows the profile of a further embodiment of a multi-chamber flat tube as per the second variant of the first part of the invention;

FIG. 7A,

FIG. 7B show two modifications of the profile of a further embodiment of a multi-chamber flat tube as per the second variant of the first part of the invention;

FIG. 8 shows the profile of an embodiment of a multi-chamber flat tube as per a third variant of the first part of the invention;

FIG. 9 shows the profile of a further embodiment of a multi-chamber flat tube as per the third variant of the first part of the invention;

FIG. 10 shows the profile of a further embodiment of a multi-chamber flat tube as per the third variant of the first part of the invention;

FIG. 11 shows the profile of an embodiment of a multi-chamber flat tube as per a fourth variant of the first part of the invention;

FIG. 12 shows the profile of an embodiment of a multi-chamber flat tube in profile as per a fourth variant of the first part of the invention;

FIG. 13 shows the profile of a further embodiment of a multi-chamber flat tube as per the fourth variant of the first part of the invention;

FIG. 14 shows the profile of a further embodiment of a multi-chamber flat tube as per the fourth variant of the first part of the invention;

FIG. 15 shows a first embodiment of a double-walled multi-chamber flat tube as per the second part of the invention;

FIG. 16 shows a further embodiment of a double-walled multi-chamber flat tube as per the second part of the invention;

FIG. 17 shows a further embodiment of a double-walled multi-chamber flat tube as per the second part of the invention.

FIG. 1 shows the profile of a multi-chamber flat tube V1, having a first chamber 1 and a second chamber 2, in the present case for holding the flow of an exhaust gas and/or charge air in a heat exchanger. The multi-chamber flat tube V1 of FIG. 1, like the multi-chamber flat tubes V2 to V17 of FIG. 1 to FIG. 17, may serve in the present case as a flow duct in a block for the separate guidance of the exhaust gas and/or charge air and of a coolant in a housing of the heat exchanger. Depending on the application, the multi-chamber flat tube may be arranged in a suitable way with a plurality of other multi-chamber flat tubes, with the chambers 1, 2 being provided so as to be traversed by the exhaust gas and/or charge air and with the outer space of the multi-chamber flat tube in the housing being provided to be traversed by the coolant. For flow optimization with regard to a flow resistance on the one hand and an improved heat exchanging capacity on the other hand, the multi-chamber flat tube V1 and also the further multi-chamber flat tubes V2 to V17 which are explained below may be provided with a suitable type and number of structure elements (not illustrated in any more detail) in order to improve the exchange of heat between the exhaust gas and/or inlet air and the coolant. In order to keep a flow resistance particularly low on the other hand, it is also possible for an outwardly pointing tube outer surface, which faces away from the chambers 1, 2, and/or a tube inner surface, which faces toward the chambers 1, 2, to be of smooth design.

The multi-chamber flat tube V1, like the further explained multi-chamber flat tubes V2 to V17, may be produced in a particularly simple manner within the context of a bending, folding and crimping process—similarly in principle to that described in U.S. Pat. No. 6,615,488 B2—with the deformation of the sheet-metal strip however taking place in a modified form in the region of the web 3.

The multi-chamber flat tube V1, like the further multi-chamber flat tubes V2 to V17 explained below, has a first wide wall 4 and a second wide wall 6 which are situated opposite one another and which are connected to one another by means of opposite narrow walls 5, 7 which form in each case one deformation region, with the wide walls 4, 6 and the narrow walls 5, 7 forming outer sides of the profile.

The first wide wall 4 is formed by an inner section of the sheet-metal strip which is situated between side sections of the sheet-metal strip. The second side wall 6 is formed, in a first region 6A, with a first side section, which is arranged to the side of the inner section, of the sheet-metal strip, and in a second region 6B, with a second side section, which is arranged to the side of the inner section, of the sheet-metal strip.

In the multi-chamber flat tube V1 shown in FIG. 1, as is the case in the further multi-chamber flat tubes V2 to V17 which are explained, the first and the second wide walls are connected by means of a web 3 which separates the at least two chambers and which forms an inner side of the profile. In the multi-chamber flat tube V1 explained in FIG. 1—as is the case in the multi-chamber flat tubes V2 to V14 explained in FIG. 2 to FIG. 14—the web 3 is formed by an edge section 3B of the second side section, which is assigned to the second region 6B. Only the edge section 3B, which is assigned to the side section of the region 6B, runs continuously from an inner side of the second wide wall 6 to the inner side of the first wide wall 4, and is connected there, in the present case by means of a soldered connection, to the first wide wall 4 at a contact point 8. In a way which follows the concept of the invention and which improves the tensile action of the web 3, the edge section 3B of the profile V1 is in the present case formed by a first deformed section 3B.1 and a second deformed section 3B.2 by means of corresponding bending processes of the edge section 3B. The first deformed section 3B.1 forms, with the edge section 3A of the other side section which is assigned to the first region 6A, a contact surface 9. In the present case, the first deformed section 3B.1 and the edge section 3A are soldered to one another at the contact surface 9. Furthermore, a soldered connection is likewise provided at that side 9.1 of the contact surface 9 which opens in the direction of the second wide wall 6, which soldered connection ends flush with the outer side of the second wide wall 6. The second deformed section 3B.2 is particularly advantageously soldered with its contact surface 9 which faces toward the inner side of the first wide wall 4. As a result of the soldering of the contact surfaces 9, 8 —instead of the soldering of mere abutting surfaces as in the prior art—a particularly high level of compressive strength is obtained in the multi-chamber flat tube V1 in the present case. Furthermore, in following the concept of the first variant of the invention, that deformed section 3B.1 of the continuously running edge section 3B which forms the contact surface 9 is aligned obliquely with respect to the second wide wall 6, with the second deformed section 3B.2 running obliquely with respect to the first deformed section 3B.1.

In the multi-chamber flat tubes V1 to V17 explained below in FIGS. 2 to 17, the same reference symbols are used for identical parts or parts with identical function.

FIG. 2 shows a multi-chamber flat tube V2 in which—again following the concept of the first variant of the invention—the first deformed section 3B.1, which forms the contact surface 9, runs obliquely with respect to the second wide wall 6, with the second deformed section 3B.2 running at right angles to the deformed section 3B.1. Again, only the edge section 3B is formed as a section which runs continuously from the second wide wall 6 to the first wide wall 4 and which forms the web 3 and which is cohesively connected at a contact point 8. In the multi-chamber flat tube V2 illustrated in FIG. 2, the contact point 8 is formed by means of a contact region of a deformed edge between the deformed section 3B.1 and the deformed section 3B.2. In the present case, the other edge section 3A, which is assigned to the side section of the region 6A, has a first deformed section 3A.1 and a second deformed section 3A.2, with the first deformed section 3A.1 forming, with the deformed section 3B.1, a contact surface 9 which also continues as a contact surface between the first deformed section 3A.2 and the deformed section 3B.2. In the present case, therefore, v-shaped deformed sections 3B.1, 3B.2 and 3A.1, 3A.2 which are aligned at right angles to one another are formed, with the edge sections 3B, 3A bearing against one another in a v-shaped contact surface 9 and with the other edge section 3A being placed in the continuously running edge section 3B. This realization of an interlocking, continuous edge section 3B and other edge section 3A thereby advantageously provides a tension rod action which increases the compressive strength of the multi-chamber flat tube V2 even against the latter being pulled apart laterally, that is to say against tension in the direction of the narrow walls 5, 7. The contact surface 9 of the multi-chamber flat tube V2 may therefore, though need not necessarily, be solder-plated. In contrast, to realize the tension rod action of the multi-chamber flat tube V1 shown in FIG. 1, solder-plating of the contact surface 9 is a prerequisite.

FIG. 3 shows an embodiment of a multi-chamber flat tube V3, similar to the multi-chamber flat tube V2 shown in FIG. 2, in which, with an otherwise similar design, the continuous edge section 3B additionally has a first deformed section 3B.1, a second deformed section 3B.2, a third deformed section 3B.3 and a fourth deformed section 3B.4. The second and third deformed sections 3B.2, 3B.3 are in the present case formed as a folded arrangement of sections, and lead the v-shaped limbs of the edge section 3B back toward the deformed section 3B.4, which advantageously forms a large-area contact region at the contact point 8 with respect to the first wide wall 4. As a result of the increase in the area of the contact point 8 in relation to the contact point 8 shown in the multi-chamber flat tube V2 of FIG. 2, the fastening of the web and therefore the compressive strength in the direction of the wide walls 4, 6 is increased yet further here.

FIG. 4 to FIG. 7B show multi-chamber flat tubes V4 to V7B which, in the realization of embodiments of the second variant of the invention, have a continuously running edge section 3B which has deformed sections which are arranged in a v-shape, s-shape, u-shape or o-shape or so as to be wound or folded and which are explained in more detail below. In a particularly advantageous way, in the multi-chamber flat tubes V4 to V7B shown in FIG. 4 to FIG. 7B, in each case one first deformed section 3B.1 is additionally aligned at right angles to the second wide wall 6, which permits, in a particularly simple manner, the realization of an edge section 3A which is formed with only one deformed section aligned at right angles, in order to realize the contact surface 9 between the deformed section 3B.1 and the edge section 3A.

In the multi-chamber flat tube V4 shown in FIG. 4, a comparatively soft or flexible tension rod in the form of the web 3 between the first wide wall 4 and the second wide wall 6 is formed by means of the indirect structure element, which is formed in the present case as a folded portion, of the deformed sections 3B.2, 3B.3. The continuous edge section 3B additionally has an s-shaped structure—aligned horizontally—in the form of the fourth deformed region 3B.4 and 3B.5, with the fifth deformed region 3B.5—in a similarly advantageous way to that explained above—forming a contact point 8 in the form of a contact surface with respect to the inner wall of the first wide wall 4.

FIG. 5 shows a further embodiment of a multi-chamber flat tube V5, in which the continuous edge section 3B is formed by deformed sections 3B.1, 3B.2 and 3B.2 which, as an indirect structure element, form an s-shaped structure—this time aligned vertically—in particular in order to realize a comparatively soft or flexible tension rod action between the first wide wall 4 and second wide wall 6.

The multi-chamber flat tubes V6, V7A, V7B shown in FIG. 6 to FIG. 7B, following the concept of the second variant, likewise realize a comparatively soft or flexible tension rod in the form of a web 3, with a contact point 8 with respect to the first wide wall 4 also advantageously being formed, in a particularly reliable way, as a contact surface. Furthermore, a lateral tensile action, which acts in the direction of the narrow walls 5, 7, of the web 3 is increased in that the edge section 3A—following the same principle to that explained on the basis of FIG. 2 and FIG. 3—is in engagement with the edge section 3B. The engagement is in the present case formed by deformed sections 3B.1, 3B.2, 3B.3, which are arranged in a u-shape, of the edge section 3B. To realize a winding, the deformed section 3B.3 is additionally part of a folded portion which is realized by the deformed portion 3B.4. The transition between the deformed sections 3B.3 and 3B.4 may, though need not necessarily, be cohesively connected at a contact point 8.1 to the second wide wall 6. The winding is guided with a further deformed section 3B.5—which is arranged at right angles to the deformed section 3B.4 and as the deformed section 3B.5 which forms the contact point 8—and final deformed section 3B.6 which closes off the winding. The deformed sections 3B.2 up to the edge-side deformed section 3B.6 thus form a closed, wound structure which is approximately o-shaped.

FIG. 7A shows an embodiment of a multi-chamber flat tube V7A in which the indirect structure element of the web 3 in the edge section 3B is—instead of being o-shaped as in FIG. 6—formed so as to be u-shaped with deformed sections 3B.3, 3B.4, 3B.5, with the deformed section 3B.5 forming an areal contact point with respect to the first wide wall 4. In contrast to the embodiment shown in FIG. 6, in the multi-chamber flat tube V7A, the folded portion between the deformed sections 3B.3 and 3B.4 is not completely closed, but rather the deformed sections 3B.3 and 3B.4 have an acute angle. This realizes the engagement structure explained in connection with FIG. 6, which permits the advantageous engagement of the edge section 3A into the edge section 3B in order to increase the tension rod action of the web 3 in the direction of the narrow walls 5, 7 too. The contact point 8.2 may, with a form-fitting connection, again serve to increase the tension rod action in the vertical direction.

The embodiment of a multi-chamber flat tube V7B shown in FIG. 7B corresponds substantially to the embodiment of the multi-chamber flat tube V7A of FIG. 7A, wherein in contrast, the deformed region between the deformed sections 3B.3 and 3B.4 no longer forms a contact point like the contact points, denoted by 8.1 and 8.2, in FIG. 6 and FIG. 7A, but rather instead is arranged at a spacing 8.3 from the inner side of the second wide wall 6. In the embodiment of the multi-chamber flat tube V7B shown in FIG. 7B, there is no longer the possibility of cohesively fastening a contact point 8.1, 8.2 to an inner side of the second wide wall. Instead, the spacing 8.3 further increases the flexibility of the continuous edge section 3B which is formed as an indirect structure.

The functional principle of an engagement structure of the edge section 3A into the edge section 3B is nevertheless realized by means of a correspondingly virtually u-shaped arrangement of the deformed sections 3B.1, 3B.2 and 3B.3, which maintains the explained lateral tension rod action of the web 3 without it being necessary to provide additional solder plating.

FIG. 8 to FIG. 10 show embodiments of multi-chamber flat tubes V8 to V10 as per the concept of the third variant of the invention, in which an edge section 3A of the other side section which is assigned to the region 6B does not have a deformed section and is in fact part of the second region 6B of the second wide wall 6. The embodiments of the multi-chamber flat tubes V8 to V10 are therefore particularly easy to produce, since the edge region 3A is undeformed and is formed directly as part of the second region 6B of the second wide wall 6. Only the continuous edge section 3B is formed in the present case as a deformed strip edge with deformed sections 3B.1, 3B.2 and 3B.3. In the multi-chamber flat tubes V8, V9, V10, each of the deformed sections 3B.1 and 3B.2 advantageously forms the contact surface 9 between the edge section 3A and the deformed section 3B.2. The deformed sections 3B.1 and 3B.2 for this purpose form a latch-like element with a stop for the edge section 3A. In the embodiment of the multi-chamber flat tube V9 in FIG. 9, the deformed section 3B.2 is adjoined by a fold structure, which is aligned perpendicular to the wide wall 4, 6, by means of a deformed section 3B.3 and 3B.4, with the fold structure forming a contact point 8 with respect to the first wide wall and—in addition to the multi-chamber flat tube V8—forming a contact point 8.1 with the second wide wall 6 by means of the abutment edge of the deformed section 3B.4.

In the embodiment of a multi-chamber flat tube V10 shown in FIG. 10, a similar fold structure is arranged horizontally with respect to the first wide wall 4 and second wide wall 6 and is formed by deformed sections 3B.2 and 3B.3, with a further deformed section 3B.4 advantageously engaging behind a folded-in portion 4.1, which is formed as a partial web, of the first wide wall 4. The principle of a lateral tension rod, which prevents the lateral tensile action, in the form of the web 3 is thus realized once again. Nevertheless, in the embodiment of the multi-chamber flat tube V10 shown in FIG. 10, only the edge section 3B is an edge section which extends continuously from the second wide wall 6 to the first wide wall 4. In the multi-chamber flat tubes V8 to V10, a contact point 8 is formed in each case by means of a linear contact region. In the multi-chamber flat tube V8, this is an abutment edge of the continuously running edge section 3B. In the multi-chamber flat tube V9 in FIG. 9, this is a deformed region of the continuously running edge section 3B between the deformed sections 3B.3 and 3B.4. In the multi-chamber flat tube V10 in FIG. 10, this is the contact line at the contact point 8 between the fold structure 4.1 and the lateral surface of the deformed section 3B.3. In the embodiment of a multi-chamber flat tube V10 shown in FIG. 10, double-sided solder plating is dispensed with in contrast to the multi-chamber flat tube V9, and a tension rod action even in the lateral direction is nevertheless ensured.

The multi-chamber flat tubes V8 to V10 are therefore embodiments which are comparatively simple to produce—as per the concept of the third variant of the invention—with the design of the continuous edge section 3B nevertheless forming a substantially indirect structure which leads to the preferred, rather soft or flexible tension rod action—similarly to that in the embodiments V4 to V7. It has been proven that, by providing an indirect structure of said type—that is to say following the concept of the second variant of the invention—a multi-chamber flat tube can be calibrated in a particularly simple manner, that is to say a contact region 8 is ensured in a particularly reliable manner by means of a slight oversize of the deformed sections 3B, 3B.1 etc. which are formed by folding or bending. In addition, it is also possible for a contact surface 9 between the edge section 3A and the edge section 3B or a corresponding deformed section 3B.2 to be realized in a particularly reliable manner.

The embodiments of multi-chamber flat tubes V11 to V14—following the concept of the fourth variant—realize particularly simple embodiments in which a continuous edge section 3B as shown in the embodiment V11 forms, with deformed sections 3B.1 and 3B.2, an angular structure, while the edge section 3A is formed as a strip end which is bent over only once, that is to say has an 1-shaped profile. Again, a contact surface of the edge section 3B makes contact with the first wide wall 4 at the inner side only at the contact point 8. In the embodiments of the multi-chamber flat tubes V11 and V12, a tension rod action can additionally be ensured in a special way by means of a double-sided solder plating, in particular at the contact point 8 and the contact surface 9.

As shown in the multi-chamber flat tube V12, the edge section 3A may also be supplemented by a further deformed section 3A.2, that is to say to form an L-shaped profile, or as shown in the embodiment of the multi-chamber flat tube V14 in FIG. 14, by a fold structure with a deformed section 3A.2.

It is likewise possible additionally or alternatively to the above-stated measures, as shown by way of example in FIG. 12, FIG. 13 and FIG. 14, for the 1-shaped structure of the continuous edge section 3B to be supplemented by a further deformed section 3B.3, which forms a fold together with the deformed section 3B.2. In this way, similarly to the deformed section 3B.2 in FIG. 11 and FIG. 12, the deformed section 3B.3 now forms a contact point 8 with respect to the inner side of the first wide wall 4.

FIG. 15 to FIG. 16 show embodiments of multi-chamber flat tubes V15, V16, V17 which realize, by way of example, the concept of the second part of the invention, in which a multi-chamber flat tube is of double-walled design and, accordingly, a web 3 is of at least double-walled design with the involvement of said chamber walls, and no edge section runs continuously between the wide walls 4, 6. In the multi-chamber flat tubes V15 and V16, the profile is wound from a sheet-metal strip, wherein in the embodiment shown in FIG. 15 the web 3 is formed exclusively by the winding structure, while the web 3 is adjoined by an edge section 3A of those side sections which are assigned to the regions 6A, 6B. Here, an edge section 3A abuts with an abutment edge against the web.

In a modification of this, in the embodiment shown in FIG. 16, the web 3 is formed with four walls, with the two central walls of the web 3 being formed by a folded-in portion 3.1 and the two outer walls of the web 3 being formed as part of the winding. In addition, an edge section 3A is formed so as to bear with a contact surface against the web only in the lower part of the web 3, adjoining the web 3. Here, an abutment edge of the edge section 3 is exposed in the edge direction of the web 3.

FIG. 17 shows a development of the multi-chamber flat tube shown in U.S. Pat. No. 6,615,488 B2, in which a web 3 is of four-walled design and the multi-chamber flat tube V17 is constructed substantially from three profiles. Here, the third profile V17.3 is formed as described in U.S. Pat. No. 6,615,488 B2, while to improve the compressive strength the profile V17.3 has inserted concentrically into it a further inner profile V17.1 to form the first chamber 1 and a further inner profile V17.2 to form the second chamber 2. This has the particular advantage that it is possible to form structures in the inner region of the chambers 1, 2 and it is nevertheless possible to provide a smooth surface at the outside, that is to say on that outer surface of the profile V17.3 which faces toward the environment, in order, for example, to apply corrugated solder or the like there. Such a design of the multi-chamber flat tube—similar to a duplex tube—thus advantageously allows a chamber inner side and an outer side of the multi-chamber flat tube to be designed independently in order to allow for the different flow properties and fluids. In the present case, the web 3 is specially formed in that an abutment edge of the edge section 3A is fixed to the inner side of the first wide wall 4.

It is self-evident that the embodiments explained here may also be formed so as to be reversed—horizontally and vertically—in relation to the options illustrated here, and combinations of features of all of the embodiments may also be carried out.

In summary, the invention relates to a multi-chamber flat tube V1-V17 having at least two chambers 1, 2 for holding the flow of a fluid, produced by deforming a sheet-metal strip, in particular produced in a bending and/or folding and/or crimping process, in which a closed profile is formed by: opposite wide walls 4, 6 which are connected to one another by means of opposite narrow walls 5, 7 which form in each case one deformed region, with the wide and narrow walls forming outer sides of the profile, with a first wide wall 4 being formed by an inner section of the sheet-metal strip which is situated between side sections of the sheet-metal strip, and with a second wide wall 6 being formed by side sections, which are arranged to the sides of the inner section, of the sheet-metal strip, with the first and second wide walls 4, 6 being connected by means of a web 3 which separates at least two chambers 1,2 and which forms an inner side of the profile and which is formed by an edge section 3A, 3B of at least one of the side sections, with only one of the side sections having an edge section 3B which runs continuously from the second wide wall 6 to the first wide wall 4 and is connected there in a cohesive manner, in particular by means of soldering, at a contact point 8, with the edge section 3B having at least two deformed sections 3B.1, 3B.2, 3B.3, 3B.4, 3B.5 and at least one of the deformed sections forming a contact surface a for an edge section 3A of the other side section. To improve a multi-chamber flat tube of said type, the invention provides the following possible measures, if appropriate in combination. In a first variant, that deformed section of the continuously running edge section 3B which forms the contact surface a may run obliquely (V1-V3) or at right angles (V11-V14) with respect to the second wide wall 6, and at least one further deformed section of the continuously running edge section 3B may run obliquely (V1-V3) or at right angles (V11-V14) with respect to that deformed section of the continuously running edge section 3B which forms the contact surface a. In a second variant, that deformed section of the continuously running edge section 3B which forms the contact surface a may be one of a plurality of deformed sections which are arranged in a v-shape, s-shape, u-shape or o-shape or so as to be wound or folded (V4-V7). In a third variant, it is possible for the edge section 3A of the other side section not to have a deformed section and to be part, in particular of the first or second region, of the second wide wall 6 (V8-V10). In a fourth alternative, the edge section 3A of the other side section may have only deformed sections which run at right angles or parallel to the second wide wall. The invention also encompasses a multi-chamber flat tube (V15-V17) in which at least one of the chambers is formed by a plurality of walls, in particular two walls, and the web 3 has at least two walls, and at least one edge section 3A of the side sections is fixed to the web. The invention also encompasses a corresponding heat exchanger and a corresponding use of the heat exchanger. 

1. A multi-chamber flat tube having at least two chambers for holding the flow of a fluid, produced by deforming a sheet-metal strip, in particular produced in a bending and/or folding and/or crimping process, in which a closed profile is formed by: opposite wide walls which are connected to one another by means of opposite narrow walls which form in each case one deformed region, with the wide and narrow walls forming outer sides of the profile, with a first wide wall being formed by an inner section of the sheet-metal strip which is situated between side sections of the sheet-metal strip, and with a second wide wall being formed by side sections, which are arranged to the sides of the inner section, of the sheet-metal strip, with the first and second wide walls being connected by means of a web which separates at least two chambers and which forms an inner side of the profile and which is formed by an edge section of at least one of the side sections, with only one of the side sections having an edge section which runs continuously from the second wide wall to the first wide wall and is connected there in a cohesive manner, in particular by means of soldering, at a contact point, with the continuous edge section having at least two deformed sections and at least one of the deformed sections forming a contact surface for an edge section of the other side section, wherein a) that deformed section of the continuously running edge section which forms the contact surface runs obliquely or at right angles with respect to the second wide wall, and at least one further deformed section of the continuously running edge section runs obliquely or at right angles with respect to that deformed section of the continuously running edge section which forms the contact surface, and/or b) that deformed section of the continuously running edge section which forms the contact surface is one of a plurality of deformed sections which are arranged in a v-shape, s-shape, u-shape or o-shape or so as to be wound or folded; and/or c) the edge section of the other side section does not have a deformed section and is part of the second wide wall, and/or d) the edge section of the other side section has only deformed sections which run at right angles or parallel to the second wide wall, in particular only deformed sections which are arranged in an i-shape or l-shape.
 2. The multi-chamber flat tube as claimed in claim 1, wherein the contact point is formed by means of a large-area contact region of a deformed section.
 3. The multi-chamber flat tube as claimed in claim 1, wherein the contact point is formed by means of a contact region of a deformed edge between two deformed sections.
 4. The multi-chamber flat tube as claimed in claim 1, wherein the contact point is formed by means of a contact region of an abutting edge of the continuously running edge section.
 5. The multi-chamber flat tube as claimed in claim 1, wherein a cohesive connection, in particular soldered connection, is formed on the contact surface between the at least one of the deformed sections of the continuous edge section and the edge section of the other side section.
 6. The multi-chamber flat tube as claimed in claim 1, wherein at least one of the chambers is formed so as to have one wall, in particular with a wall thickness of less than 0.2 mm.
 7. The multi-chamber flat tube as claimed in claim 1, wherein at least one of the chambers is formed by a plurality of walls, in particular two walls, in particular with a wall thickness of less than 0.2 mm, preferably wound or formed by walls which are placed concentrically one inside the other.
 8. The multi-chamber flat tube as claimed in claim 1, wherein further webs are formed by folding in the first and/or second wide wall.
 9. The multi-chamber flat tube as claimed in claim 1, wherein a tube outer surface and/or a tube inner surface is smooth.
 10. The multi-chamber flat tube as claimed in claim 1, wherein a tube outer surface and/or a tube inner surface is structured, in particular has one or more types of structure elements which are selected from the group comprising: dimples, winglets, ribs.
 11. The multi-chamber flat tube as claimed in claim 1 for conducting a fluid in a heat exchanger, in particular a first fluid, preferably in the form of an exhaust gas and/or charge air, or a second fluid, preferably a coolant.
 12. A heat exchanger for exchanging heat between a first fluid, in particular an exhaust gas and/or charge air, and a second fluid, in particular a coolant, having: a block for the separate and heat-exchanging guidance of the first and second fluids, having a number of flow ducts through which the first fluid can flow, a first chamber which holds the flow ducts and through which the second fluid can flow, a housing in which the chamber and the flow ducts are arranged; wherein a flow duct is formed in the manner of a flat tube as claimed in claim
 1. 13. The use of the heat exchanger as claimed in claim 12 as a high-temperature or low-temperature heat exchanger.
 14. The use of the heat exchanger as claimed in claim 12, in particular an exhaust-gas heat exchanger, as an exhaust-gas cooler for exhaust-gas cooling in an exhaust-gas recirculation system of an internal combustion engine of a motor vehicle.
 15. The use of the heat exchanger as claimed in claim 14, in particular an exhaust-gas heat exchanger, as an auxiliary heater for heating the interior space of a motor vehicle.
 16. The use of the heat exchanger as claimed in claim 12 AS a charge-air cooler for the direct or indirect cooling of charge air in a charge-air supply system for an internal combustion engine of a motor vehicle.
 17. The use of the heat exchanger as claimed in claim 12 as an oil cooler, in particular for cooling engine oil and/or transmission oil.
 18. The use of the heat exchanger as claimed in claim 12 as a refrigerant or coolant cooler and/or refrigerant or coolant condenser in a refrigerant or coolant circuit of an air-conditioning system or of an engine cooling circuit of a motor vehicle.
 19. A multi-chamber flat tube having at least two chambers for holding the flow of a fluid, produced by deforming a sheet-metal strip, in particular produced in a bending and/or folding and/or crimping process, in which a closed profile is formed by: opposite wide walls which are connected to one another by means of opposite narrow walls which form in each case one deformed region, with the wide and narrow walls forming outer sides of the profile, with a first wide wall being formed by an inner section of the sheet-metal strip which is situated between side sections of the sheet-metal strip, and with a second wide wall being formed by side sections, which are arranged to the sides of the inner section, of the sheet-metal strip, with the first and second wide walls being connected by means of a web which separates at least two chambers and which forms an inner side of the profile, wherein at least one of the chambers is formed by a plurality of walls, in particular two walls, and the web has at least two of said walls, and at least one edge section of the side sections is fixed to the web.
 20. The multi-chamber flat tube as claimed in claim 19, wherein at least one of the chambers is wound with a plurality of walls, in particular two walls, in particular the web has at least two walls which are formed as part of the winding.
 21. The multi-chamber flat tube as claimed in claim 19, wherein two walls of the web are formed by means of a folded-in portion.
 22. The multi-chamber flat tube as claimed in claim 19, wherein at least one of the chambers is formed by a plurality of walls which are placed concentrically one inside the other, in particular two walls, in particular the web has at least two walls which are formed as part of the walls which are placed one inside the other.
 23. The multi-chamber flat tube as claimed in claim 19, wherein an edge section of at least one of the side sections adjoins the web, in particular the edge section abuts with an abutment edge against the web.
 24. The multi-chamber flat tube as claimed in claim 19, wherein the web is formed by an edge section of at least one of the side sections, in particular the edge section bears with a contact surface against the web.
 25. The multi-chamber flat tube as claimed in claim 19, wherein an abutment edge of the edge section is exposed.
 26. The multi-chamber flat tube as claimed in claim 19, wherein an abutment edge of the edge section is fixed to the first wide wall.
 27. The multi-chamber flat tube as claimed in claim 19, wherein a wall thickness is formed so as to be less than 0.2 mm.
 28. The multi-chamber flat tube as claimed in claim 19, wherein a cohesive connection, in particular soldered connection, is formed on one or more contact surfaces or points between walls.
 29. The multi-chamber flat tube as claimed in claim 19, wherein further webs are formed by folding in the first and/or second wide wall.
 30. The multi-chamber flat tube as claimed in claim 19, wherein a tube outer surface and/or a tube inner surface is smooth.
 31. The multi-chamber flat tube as claimed in claim 19 for conducting a fluid in a heat exchanger, in particular a first fluid, preferably in the form of an exhaust gas and/or charge air, or a second fluid, preferably a coolant.
 32. A heat exchanger for exchanging heat between a first fluid, in particular an exhaust gas and/or charge air, and a second fluid, in particular a coolant, having: a block for the separate and heat-exchanging guidance of the first and second fluids, having a number of flow ducts through which the first fluid can flow, a first chamber which holds the flow ducts and through which the second fluid can flow, a housing in which the chamber and the flow ducts are arranged; wherein a flow duct is formed in the manner of a flat tube as claimed in claim
 19. 33. The use of the heat exchanger as claimed in claim 32 as a high-temperature or low-temperature heat exchanger.
 34. The use of the heat exchanger as claimed in claim 32, in particular an exhaust-gas heat exchanger, as an exhaust-gas cooler for exhaust-gas cooling in an exhaust-gas recirculation system of an internal combustion engine of a motor vehicle.
 35. The use of the heat exchanger as claimed in claim 34, in particular an exhaust-gas heat exchanger, as an auxiliary heater for heating the interior space of a motor vehicle.
 36. The use of the heat exchanger as claimed in claim 32 as a charge-air cooler for the direct or indirect cooling of charge air in a charge-air supply system for an internal combustion engine of a motor vehicle.
 37. The use of the heat exchanger as claimed in claim 32 as an oil cooler, in particular for cooling engine oil and/or transmission oil.
 38. The use of the heat exchanger as claimed in claim 32 as a refrigerant or coolant cooler and/or refrigerant or coolant condenser in a refrigerant or coolant circuit of an air-conditioning system or of an engine cooling circuit of a motor vehicle. 